<html>

<head>
    <meta charset="utf-8" />
    <title>这是标题</title>
</head>



<body>
    <!-- 单选下拉框 -->
    <form action="#" method="get">
        <select name="sex">
            <option value="1">男</option>
            <option value="2">女</option>
        </select><br>

        <input type="submit" value="提交选择">
    </form>
    <br>
    <br>
    <br>
    <br>
    <!-- 多选下拉框 -->
    <form action="#" method="get">
        <select name="hobby" size="3" multiple>
            <option value="1">抽烟</option>
            <option value="2">喝酒</option>
            <option value="3">打麻将</option>
        </select><br>

        <input type="submit" value="提交选择">
    </form>
</body>

</html>